This application claims priority to European Patent Application Serial No. 12382233.0, which was filed Jun. 7, 2012. This priority application is hereby incorporated by reference in its entirety into the present application, to the extent that it is not inconsistent with the present application.
Generators may be used to supply an uninterrupted supply of power to an electric power load in many applications. However, it may be impractical or undesirable to use a single generator as an electrical power supply for an electric power load in certain circumstances. For example, a single generator may be incapable of generating a sufficient amount of electrical power to meet the electric power load requirements. Consequently, many power systems include multiple generator sets for supplying electrical power to electric power loads. Such power systems may include generator sets connected in parallel with an electric bus and configured to supply power to the electric bus.
In addition, connecting multiple generator sets in parallel may provide for an inherent redundancy in the power system. Such an inherent redundancy may be desirable in applications requiring uninterrupted supply of electrical power. If a generator set fails, the electric power load may be redistributed to the other generator sets in the power system such that electrical power is maintained in the system. Furthermore, the electric power load in certain applications may vary over time, resulting in an increased demand for electrical power on the system. Power systems having multiple generator sets configured in parallel may be desirable as additional generator sets may be connected in parallel to provide additional electrical power to the increased load. Conversely, if the electric power load decreases, one or more of the generator sets may be removed from the power system and utilized in another power system. Such flexibility in the use of the generator sets may be desirable in the electrical power industry.
Typically, each generator set connected to a load or utility grid includes a controller configured to monitor and control the generator set independently of the other generator sets connected to the load or utility grid. A central controller may be operatively coupled to each generator set controller to provide a central system control for monitoring and controlling one or more of the generator sets in the power system. The central controller may assist in the coordinated operation of the generator sets in the power system, which may save time and resources.
In such a central system control, analog controllers and associated components may be used in the controlling and monitoring of individual generator sets, or the collective set of generator sets, in the power system. Typically, analog controllers include a dual discrete design, such that duplicate input transformers and circuitry may be required when additional features are added. Such added circuitry and components may increase the cost and space required of the system, which may be undesirable in the power system design. In addition, in such a central system control employing analog controllers, the connected generator sets typically are operated in a similar mode, such that operation of two or more generator sets in the system in a different mode is unavailable. Further, in a central system control employing analog controllers, additional components are generally required when operating in a load sharing mode of operation, which increases costs and maintenance requirements of the central system control.
What is needed, then, is a power system including a compact, reliable, and efficient load sharing system having a plurality of generator sets connected in parallel and one or more controllers, configured to monitor and control the load sharing of the power system utilizing a minimum number of controller components.